The present invention generally relates to a receptacle with ground fault interruption function, and more specially, to a receptacle with ground fault interruption function which is suitable to be mounted into ordinary walls.
With people""s living standard continuously rising and household electrical appliances being daily-increasingly popularized, the consumer demands that some electrical receptacles be pre-installed in walls when their houses are being built. However, at the present time, most of the electrical receptacles embedded in the walls are ordinary electrical receptacles and do not have ground fault interruption function. Although some of the electrical receptacles, for example, as those disclosed in U.S. Pat. No. 4,237,435 and in U.S. Pat. No. 4,247,840, have ground fault interruption function, they still have the following shortcomings:
(1) The electrical receptacle disclosed in U.S. Pat. No. 4,237,435 and in U.S. Pat. No. 4,247,840 will be cut-off immediately, when some component in operation is damaged. But its power input and output terminals might still be electrically connected to power source when the reset button of the receptacle is pushed down to reset the receptacle.
(2) In installing such an electrical receptacle, the installing worker can wrongfully connect the power source input terminal with the power source output terminal in the receptacle because the installing worker is unable to correctly distinguish between the power input terminal and the power output terminal, thereby connecting the power input terminal with receptacle""s output terminal and connecting the power output terminal with receptacle""s input terminal. Under such a condition, the receptacle with ground fault interruption function can still connect its input and output terminals with the power source. Under this condition, not only the electrical receptacle is unable to perform ground fault interruption function, it also misguides the users to continuously use this wrongfully connected receptacle. Thus it may cause harm to the users and damages and the household electrical appliances.
The object of the present invention is to provide a new and improved receptacle that is suitable to be installed within ordinary walls and ordinary wall outlet boxes. Even when a component in the receptacle is damaged or a wrongful connection, as above described, is made. This receptacle can still prevent the power input from being connected to power output.
To achieve the above-described objective, the receptacle of the present invention comprises:
an upper housing 2, a middle supporter 3 and a lower holder 4;
a metal mounting plate 1 disposed between said middle supporter 3 and said upper housing 2;
a printed circuit board 18, thereon are disposed a differential transformer 19, a reset guide member 28;
a solenoid 26 within which an iron core is inserted;
a flat spring type of resilient off locking switch 37 made of resilient metal material and disposed between the reset guide member 28 and said printed circuit board 18;
a contact 38 positioned corresponding to said protruded circular spot 39.
a longitudinally central through hole 29 formed within said reset guide member 28;
a movable L-shaped metal latch member 30 disposed under said reset guide member 28, and a position-limiting pin 32 for limiting the displacement of said L-shaped metal latch member 30 disposed at one end of said latch member 30;
a central aperture 31 formed at the horizontal part of said latch member 30;
a locking guide plunger 35, a flat surface 41 formed at the bottom end of said locking guide plunger 35, and a locking recess 36 formed near the under part of said locking guide plunger 35;
a spring member 91 worn over the upper part of said locking guide plunger 35, and one end of said spring member 91 inserted within a reset button 8;
one end of said of resilient locking switch 37 is welded or soldered on said printed circuit board 18 and a protruded circular spot 39, formed by punching, is disposed on the another end of said locking switch 37; and
a contact 38 placed corresponding to said protruded circular spot 39; and through said differential 19, both ends of said off locking switch 37 are connected to their respective the neutral lines of the power-input connectors 9, 10 and power-output connectors 109, 110.
By using the above-described arrangement, the present invention provides more reliable protection to consumer and appliance in installing and using the ground fault interruption receptacle.